1. Field of the Invention
The present invention relates to a technique for determining the collision particulars of a vehicle.
2. Description of the Related Art
In prior art, a variety of vehicle impact sensors configured to detect the occurrence of a collision at the time of a vehicular accident are known. For example, in JP, A, 07-172262 described below, there is disclosed a system configured to detect a side collision using a G sensor and contact sensor that are activated at the time of vehicular side collision. However, in a system that restrains a vehicle occupant at the time of a vehicular accident based on an occupant restraint system such as an airbag module, an advanced detection technique capable of immediately detecting the occurrence of vehicle collision to improve occupant restrainability has been desired. In particular, for a side collision such as described in JP, A, 07-172262, only a vehicle door exists between a vehicle occupant and a colliding object and, in the event of a pole collision in which the colliding object having a pole-like shape, such as a telephone pole or standing tree, collides with the vehicle door from the side, the high penetration velocity from the door toward the vehicle interior requires determination of the side collision particulars in a shorter period of time than a front collision. In addition, when the colliding object is pole-like in shape, the effect on the vehicle occupant at the time of a side collision is known to be higher than that when the colliding object is barrier-like in shape, such as a wall or another vehicle, resulting in the need for a technique that appropriately controls the form of restraint on the vehicle occupant at the time of a side collision in accordance with the colliding object type.